boon
n. countablen. a helpful thing or person that makes life easier. You use this word when something is very useful or lucky for you.
n. a source of help, benefit, or good fortune. Often used with the preposition 'to' or 'for' to indicate the recipient of the benefit.
The new library is a boon to students.
The sudden rain was a boon to the farmers who had been waiting for water.
The invention of the printing press was a boon to the spread of knowledge across Europe.
From Middle English boon (“prayer”), from Old Norse bón (“prayer, petition”), from Proto-Germanic *bōniz (“supplication”), influenced by boon (“good, favorable”, adjective). Doublet of ben; see there for more.
From Middle English boon, bone, borrowed from Old Northern French boon, from Old French bon (“good”), from Latin bonus (“good”), from Old Latin duonus, dvenos, from Proto-Indo-European *dū- (“to respect”).
From Middle English bone (“reed, stem, husk”), akin to or alteration of Old English bune (“reed; drinking cup”).